: Navigate to the launcher settings and enable the "Show historical versions" checkbox. This allows you to select early Alpha and Beta versions from the version list. Custom JAR Installation
This version is based on Alpha 1.2.6, which sometimes requires a custom file to bypass the official launcher's asset checks. Black Screen: Ensure you have allocated at least 512MB–1GB of RAM minecraft alpha 0.0.0 pojavlauncher
You're referring to a very early version of Minecraft! Minecraft Alpha 0